1. Field of the Invention
This invention relates to a wake-up system multiplexing technique for obtaining status of a plurality of switches, disposed at remote locations of a monitored region, and connected to a controller by a single wire bus and more particularly to an automatic wake-up system which turns on the controller in responses to actuations of any one of a chosen number of high priority switches.
2. Description of the Prior Art
Switch monitoring systems normally operate after an operator initiates a POWER-ON switch to start a POWER-ON sequence in a computer or microcontroller. A problem exists when a need occurs for the system to self-initiate the POWER-ON sequence of the computer.
In an effort to develop a system that would automatically wake-up and initiate a multiplex monitoring operation of a plurality of switches, a search was initiated for a scheme that uses several high priority switches which, if activated, would wake-up a microcontroller and cause multiplex monitoring of all the remaining switches connected to the single wire bus. That search resulted in the automatic wake-up circuit of the present invention.